Red flags presented in current low back pain guidelines: a review

The purpose of this study was to identify and descriptively compare the red flags endorsed in guidelines for the detection of serious pathology in patients presenting with low back pain to primary care. We searched databases, the World Wide Web and contacted experts aiming to find the multidisciplinary clinical guideline in low back pain in primary care, and selected the most recent one per country. We extracted data on the number and type of red flags for identifying patients with higher likelihood of serious pathology. Furthermore, we extracted data on whether or not accuracy data (sensitivity/specificity, predictive values, etc.) were presented to support the endorsement of specific red flags. We found 21 discrete guidelines all published between 2000 and 2015. One guideline could not be retrieved and after selecting one guideline per country we included 16 guidelines in our analysis from 15 different countries and one for Europe as a whole. All guidelines focused on the management of patients with low back pain in a primary care or multidisciplinary care setting. Five guidelines presented red flags in general, i.e., not related to any specific disease. Overall, we found 46 discrete red flags related to the four main categories of serious pathology: malignancy, fracture, cauda equina syndrome and infection. The majority of guidelines presented two red flags for fracture ('major or significant trauma' and 'use of steroids or immunosuppressors') and two for malignancy ('history of cancer' and 'unintentional weight loss'). Most often pain at night or at rest was also considered as a red flag for various underlying pathologies. Eight guidelines based their choice of red flags on consensus or previous guidelines; five did not provide any reference to support the choice of red flags, three guidelines presented a reference in general, and data on diagnostic accuracy was rarely provided. A wide variety of red flags was presented in guidelines for low back pain, with a lack of consensus between guidelines for which red flags to endorse. Evidence for the accuracy of recommended red flags was lacking.